Hello,
I’m new to the Scrivener world, and just downloaded the Windows beta version last week in anticipation for Nanowrimo. I use a Windows Vista laptop for probably 80% of my writing at home and on the go. However, I use a Mac at work running on PowerPC processor, and I downloaded the 2.0 trial, to be able to write over lunch breaks. I thought I’d be able to write on the Windows Beta from my laptop, save my project to Dropbox, and then open that project on the Mac. However, when I open the project file on the Mac, I get the following message: “An exception was thrown while trying to open the project ‘nanowrimo2010.scriv’. The project date may have become corrupted. Try restoring from a backup, or create a new project and use File>Import>Scrivener Project to retrieve work from this project (structure information may be lost).” And then the program proceeds to close and prompts me to send a crash report to Apple.
This is the second day I have attempted to open the project. After receiving this message yesterday, I went home and opened the project without difficulty on the Windows laptop. I promptly made a second copy of the project, renaming it (thinking that it might be the issue). And so today I have gotten this same message.
I did attempt to use the File > Import > Scrivener Project instructions, however “Scrivener Project” isn’t an option in the Mac version when I follow this.
I was wondering if there is a process or step that I’m missing, or if I’m just not going about this the right way to begin with.
Advice is appreciated. 
Thanks,
Tara